A Patient with Slowly Progressive IDDM Developed Overt Insulin Dependence Simultaneously with Thyrotoxicosis in the Postpartum Period

Abstract

A 23-year-old woman experienced two episodes of thyrotoxicosis, the first 1.5 years before pregnancy and a second in the postpartum period. She was diagnosed as having diabetes at the time of recovery from the first thyrotoxic episode. She did not take any medication for her diabetes until insulin therapy was started during the third month of pregracy. Insulin was replaced with sulfonylurea compound shortly after delivery. The titer of antithyroid microsomal antibodies decreased during pregnancy with a rebound increase after delivery. Three months postpartum she developed diabetic ketoacidosis simultaneously with thyrotoxicosis. Thereafter, she constantly needed more than 30 U/day of insulin, and demonstrated low plasma C-peptide levels. Presence of islet-cell antibodies in her sera and HLA DR4 indicated the autoimmune nature of her diabetes. Alteration of maternal immune response caused by pregnancy might be a precipitating factor in the development of overt insulin dependence in the postpartum period. © 1989, THE JAPAN DIABETES SOCIETY. All rights reserved.